Bis-(isopropylaryl) methane



United States Patent 6 2,933,540 mm ri'zoi YLAnYmMETn A 11 Arthur R. Lydin'g, New Haven, com, to Olin Mathieson Chemical Corporation, a corporation of V No Drawing. Application January 14, 1058 Serial No. 708,750 2 c1. 264F468) This invention relates to novel bis-(isopropylaryD- methane hydrocarbons "and particularly to bis-'(iso'propylphenyl)methane, more simply termed dicumylmethane, especially isomeric mixtures of dicumylmethanes, having highly advantageous physical and chemical properties as compared with previously known bis-(alkaryl)methane hydrocarbons. V

This application is a continuation-in-part of my copending application Serial Number 598,541, filedJuly 18, 1956. p p V The principal object of this invention is the provision of novel bis=(isopropylarybmethane hydrocarbons, particularly dicumylmethane. Further objects include the provision of isomeric mixtures of dicumylmethane, and particularly of p,p-dicumylmethane.

In accordance 'with this invention, novel 'dieumylmethanes have been prepared sliccessfully and have been found to display unexpectedly favorable physical and chemical properties, such that these new compounds are exceptionallyversatile. I n p v v, p

The novel compounds of the inventionare most readily prepared by the condensation of curnene (isop'r'op'ylbenacne) with formaldehyde in the presence of eoncentrated sulfuric acid or other acidic condensing agent and, if desired, of'a solvent, such as methanol, for the'cumene.

' The resulting filylmethane has the followinggitu ture I stirred for an additional two hours at the same tempera-' ture. The mixture'was transferred to a separatory'funnel and allowed to separate-r overnight The organic layer was washed with means portions of 7% sodium carbonate and thenwitli three 50 ml. parables: water. The organic layer was drie'd' over K2603 and filtered.

The liquid was distilled. Unchanged cunieri, weighing 49 grams was recovered at 65 C./30 mm. An intermediate cut was obtained which boiled between 126 and 128 C. at a pressure of 0.5 mm. of mercury (N =1.542l) and weighed 4.3 grams. The product, weighing 36.5 grams then distilled at128 to 132 C. at

dei of refraction, N3 was 1.5403.

2,933,540 a e ted Apr. 1 9, 1s6o lCc 2 ip'r'e'ssurebr 0.5 mm. nie'r'eu'ry (-N =l'.54l2). As the "intermediate out had a refractive index close to that of the product, they wereconsideredidentical and the yield of 40.8 'grams'was thus calculated to be 66% of the theoretical (based on formaldehyde). Analysis of a heart cut gave C '90.03% and H' i9.80%. Theory requires Cfi90.42%andH 9 .59%. The congealing temperature of themixture was found to be'about +40 C.

organic layer was washed four times with 35 ml. portionsof 7% "sodium carbonatesolution, then three. times with 50ml. portions of distilled water, and dried over anhydrous potassium carbonate, t

The solution was filtered and subjected, to distillation under reduced pressure. Cumene was distilled at 65 -70 C; at a pressure .of 30 mm.v of mercury. Dicumylmethane was then distilledat temperatures of 12 6? to C. at apressure ofabout 0.5 mm. of r'nercury, the yield amounting to 37.9. g.,;63 %Jof theoretical based ontormaldehyde; Index of refraction, N5 was 1.5423.

EXAMPLES t A mixture ci iiifie'liie, 580 ciiriceiitrated suitingaci and so g. of methanol wasjwanha to 45 'o. the mixtur was stirred and maintained n45" to so" c.,o.5 more or formal ehyde wasgradua'lly added over two hours as an queous solution ciihtaii'lihg,3,6% of formaldehyde. Th e mixture stirred at 45 50? C. for an additional 2 2 hour p'fidd, and wasjthen'allowed "to, separate. The organic layer was washed three times with 50 nil, portions of 7% sodium carbonate solution, twice with 75 ml. poition's of 1% sodium 'c'lil'oride solui en'afia' then with 75 ml. of distilled water. The solutioii was thh dried over anhydrous potassium carbonate and filtered. On distillationpf the filtrate under reduced pi-ssiir ciiniene was removed andjthe'n 89.2. g., of dicuiiiylmethanewas obtained at a boiling point of 126 .to 132c.'2it 5561i: 0.5 of mercur pressure, amountin to 70.9%, of theoretical yield, based on formaldehyde. In-

In the receding ex mples, theform aldehyde may be replaced. in whole or inpa'rt by materials capable offurnishing formaldehyde, for example, by a solid polymer of formaldehyde such as parafornialdehyde or by trioxane. The dicnmylmethane product ofthe above examples QEQ-CHP'OQE and" the balance at other isomers, particularly the" 63 products: have been found to have the following physical properties; v Boiling point-326330 C./760 mm, 128132 C./0.5 mm. Congealing point 40 C. Density at 25 C.-O.9320 Refractive index N 7.54031.5429

Substantiallypure p,p'-dicumylmethane was isolated by fractional crystallization of the above isomeric mixtures. The liquid was cooled to a temperature between -30 and -40 C. and allowed to crystallize partially, seeding if necessary with a small amount of the p,p' solid isomer or of the solidified material prepared by storing the isomeric mixture at a temperature below -40 C. for several days. mother liquor by rapid filtration or centrifuging, and if desired, the crystallization process could be repeated. Material purified by crystallization in the above manner was shown to consist of purified p,p-dicurnylmethane by infrared spectroscopic analysis and capable of yielding substantially 'pure p,p' benzophenone'dicarboxylic acid on oxida tion, The recrystallized material had a refractive index N3 of 1.5405 and displayed a melting point of 30 C. and boiling point of 326 -330 C. at atmospheric pressure (760 mm. mercury).

The obtainment of predominantly, the para, para iso mer, substantially over 80%, by the condensation of cumene with formaldehyde is in contrast with the formation of only up to 30 or 40% of such isomer in the condensation of other alkylaromatic compounds, such as toluene, with formaldehyde. 7

The isomeric product is a clear and colorless liquid of low viscosity having a pungent aromatic odor and char acterized by an unusually extended liquid range at normal The crystals were separated from the r atmospheric pressure, from .40 C. to about 330 C.

Also, the"combination of low viscosity and low vapor pressure at ordinary temperatures is unusually favorable.

The novel product is therefore highly advantageous as a heat-exchange fluid, due to the above favorable properties and to its chemical stability and freedom from tures, enables the extensive spreading and penetration of the insecticide with resulting enhancement of the desired results. Illustrating the utility of dicumylmethane as a chemical intermediate, the product of Example 2 was oxidized to form benzophenone dicarboxylic acid in accordance with US. 2,806,059, as follows:

A finely dispersed stream of gaseous oxygen was passed I;

through a stirred solution of 9.5 g. of cobaltous acetate tetrahydrateand 50 g. of methyl ethyl ketone in 300 g. of glacial acetic acid contained in a reaction vessel maintained at 90 C. and'equipped with a stirrer and reflux condenser. In 60 minutes, the mixture turned green and 37.8 g. of dicumylmethane was added. The mixture was maintained at about 90 C. and the passage of oxygen was continued for 96 hours.

The reaction mixture was filtered hot and the filtered solid was washed with a small volume of concentrated. 7

HQ, then to neutrality with water, and finally with a small volume of ethanol. The white solid was dried in an oven and amounted to 13.5. g. of p,p' benzophenone dicarboxylic acid, having a melting point of 360 C.

The reaction mixture filtrate was concentrated to a half of its volume, cooled and the crystalline product was separated by filtration. After being washed with water 4 and dried, 3 g. of o,p' benzophenonedicarboxylic acid were obtained, displaying a melting point of 242-243 C.

The versatility of dicumylmethane as a chemical intermediate is shown by the fact that it can readily be oxidized by means of gaseousoxygen or air under more moderate conditions than the above to yield a bisphenol and acetone as by-product. For example, 100 g. of dicumylmethane were dispersed in 200 mi. of water containing 2 g. of sodium carbonate, 2 g. of sodium bicarbonate, 0.1 g. of sodium stearate and 0.1 g, of benzoylperoxide. Oxygen gas was passed into this well-agitated mixture maintained at about 60 C. at a rate of about 30 ml. per minute, and the reaction was allowed to continuefor about 48 hours. Sufiicient sulfuric acid was added to form a 10% solution and the well-stirred mixture was heated under reflux for 2 to 3 hours. The solution was made alkaline with sodium hydroxide and filtered. The filtrate was carbonated with Dry Ice, the solution being then extracted with ether. After evaporation of the solvent, the bisphenol wasobtained at a yield corresponding to about 70% of the dicumylmethane which had reacted. Bisphenol of the above composition on reaction with epichlorohydrin yields commercially valuable resins of the epoxy type. Likewise, glycol esters of the benzophenone dicarboxylic acids can be polymerized to yield thermoplastic resins useful for the manufacture of filaments and films.

If theabove phenolic oxidation is carried out for about 24 hours, mono-phenol of the composition (CHs)2CH fu1 ingredients of explosive compositions. The monoand di-nitro derivatives, can readily be reduced to the corresponding aromatic amines, which yield valuable dye ingredients, on diazotization and coupling, and display properties and enter other reactions typical of aromatic amines.

Likewise, chlorination in accordance with known procedures results in chloro-dicumylmethanes which may be advantageous as chemical intermediates and solvents.

-;v .From the foregoing, it will be seen-that the novel dicumylmethanes of this invention are valuable compounds, displaying considerableversatility based on the unusually favorable physical properties as well as advantageous chemical reactivity" resulting from the unique structure.

I claim:

1. Dicumylmethane consisting essentially of at least of the p,p' isomer and substantially the balance of the o,p' isomer. Y Y

2. p,p'-Dicumylmethane.

References Cited in the file ofjthis patent UNITED STATESV'VYPAYTENTS 5192b (1956); abstracted from Kim. Prom. No. .7; Octoher-November, 1955.1 

1. DICUMYLMETHANE CONSISTING ESSENTIALLY OF AT LEAST 80% OF THE P,P'' ISOMER AND SUBSTANTIALLY THE BALANCE OF THE O,P'' ISOMER. 